text: NETA, also known as norethinyltestosterone acetate, as well as 17α-ethynyl-19-nortestosterone 17β-acetate or 17α-ethynylestra-4-en-17β-ol-3-one 17β-acetate, is a progestin, or synthetic progestogen, of the 19-nortestosterone group, and a synthetic estrane steroid. It is the C17β acetate ester of norethisterone. NETA is a derivative of testosterone with an ethynyl group at the C17α position, the methyl group at the C19 position removed, and an acetate ester attached at the C17β position. In addition to testosterone, it is a combined derivative of nandrolone (19-nortestosterone) and ethisterone (17α-ethynyltestosterone).